however, the initial working at this mine did not experience strata control problem because the void remained, relatively, small resulting less disturbance in the intact overlying strata.
now the mining engineering problem has been not just the mining issues, but also to pay attention to stability and surrounding rock strata control problems.
现在的采矿工程已不仅是开采问题,而且还要注意围巖稳定性和巖层控制。
hence, strata control theory can be used in gas extraction and control of coal and gas outburst.
因此,可以利用巖层控制理论指导瓦斯抽采和预防煤与瓦斯突出的发生。
finally, the strata control observation dat shows that gateway deformation was under control by this plan, and the better economic benefit was obtained.